Autumn calving: keeping calves healthy

The first three months of a calf’s life are crucial and help determine their future health, growth and performance.

Housing management

It is important that housing management is optimised to prevent stress and to limit the calf’s susceptibility to disease. The basic requirements for every calf house are:

A constant supply of fresh air, without draughts, is essential in preventing respiratory and other diseases and in improving production.

Good ventilation removes stale, damp air, which helps ensure viruses and bacteria cannot survive for long outside the animal. Cobwebs in buildings and condensation on the underside of roofing are signs of poor ventilation.

Calves are susceptible to the chilling effects of wind and rain, so should be kept indoors or under shelter for the first three weeks of life. A comfortable microclimate must be provided, particularly in the first week of life, with temperatures under 20°C.

Regardless of housing type, a newborn calf will feel cold when the temperature is between 10°C and 15°C. Therefore, the design requirements for a dry, draught-proof environment at calf level, without decreasing the ventilation and fresh air, are extremely important.

Air inlets should be above calf height and the penning area should be laid out so that the currents of incoming air are not directed into the calf lying area.

Draughts are especially difficult to avoid in open-sided buildings where wind cannot be controlled.

Unfortunately, these types of buildings are common on suckler farms, so efforts should be made with buildings like these to build temporary walls or shelters to avoid uncontrolled wind affecting young calves.

Calves spend up to 80% of their time lying down, so the type and depth of bedding used is important. Calves should not lie directly on concrete, as it tends to become wet and slippery, causing calves to lose heat and encouraging the spread of bacteria throughout the house.

Deep straw bedding is superior to other bedding material in its efficacy as an insulator. It should be at least 15cm deep and should remain dry at all times.

Wood shavings and bark chips can be used to provide calves with dry lying conditions.

Calf health

Pneumonia

Pneumonia is one of the main causes of mortality in calves. Viruses such as RSV, Pi3 and IBR can act individually or in combination to cause significant lung and airway damage, making the calves more susceptible to secondary bacterial infections.

So, by protecting against these viruses, you can significantly reduce the number and severity of pneumonia outbreaks.

Vaccination offers protection against the most common viruses and for a quick onset of immunity, calves can be vaccinated with an intranasal vaccine. As it is given intranasally, it won’t be affected by maternal antibodies from the cow.

Protection from a single dose lasts 12 weeks and can be given from as young as two weeks of age.

There are many types of vaccines and vaccine programmes available, so to choose one that best suits your farm, it is best to discuss it with your veterinary practitioner in order to ensure you get the best results from your investment.

Scour

Calf scour is another major cause of poor performance and death in suckler calves. Whether a calf stays healthy or gets scour is determined by the balance between the resistance of the calf to infection and the level of infection to which it is exposed. Good colostrum management is the single most important factor to improve the resistance of the calf to infection.

Colostrum is the first milk that the cow produces. It is richer than normal milk in immunoglobulins (antibodies). In healthy beef cows, the colostrum quality is usually good. Problems may arise if beef cows are undernourished before calving, eg if they are put on a straw-only diet.

The ability of the calf to absorb antibodies decreases a few hours after birth and is gone in 24 hours. Antibodies cannot cross over from the cow to the calf during pregnancy and the calf is therefore born without any immunity.

If calves do not get enough antibodies through colostrum soon after they are born, they will have failure of passive transfer (FPT) of antibodies and have a high chance of becoming ill and dying. Calves that survive have poorer growth rates than calves that received adequate colostrum.

Several infectious agents can also cause scour in calves and often more than one is involved. The main causes are Cryptosporidium, Rota and Corona viruses, E coli and Coccidiosis (more common in older calves).

It is not possible to tell the cause just by looking at the scour, so if your calves have diarrhoea, a faecal sample should be collected and analysed by a laboratory to determine the cause and proper treatment needed. Calf scour vaccines are available and these work by vaccinating the dam two to 12 weeks before she calves so that the calf subsequently ingests the antibody-rich milk.

Cryptosporidiosis is an important disease in newborn calves (from one to four weeks of age) and causes damage to the small intestine, resulting in mild to severe diarrhoea, especially on farms where hygiene is poor. It is highly infectious and is very difficult to eradicate once established, as it is resistant to many disinfectants.

Calves should have access to fresh, clean water from birth, as it increases creep intake and encourages rumen development.